Presence and deleterious effect of the Russian wheat aphid, Diuraphis noxia (Mordvilko) and other cereal aphids, in the central-northern region of chile during 1990/91 and 1991/92 seasons

Mireya Zerené Z.1 y Carlos Quiroz E.2

To evaluate the incidence of Russian wheat aphid (RWA) (Diuraphis noxia (Mordvilko)) and other cereal aphids, there were developed live essays, including lields in the Metropolitan area and some coastal drylands in the VI Region. The results from La Platina Experimentai Station revealed that the level of aphids were below 10 per axis, during 1990/91 season. The predominant specie was Russian aphid, covering 66% of the total population. In Metropolitan Area late date sowings, the additive eflect of RWA and BYDV produced up to 39% of losting. In the VI Region coastal drylands the eflect of RWA was up to 18% of decrease in production relative to controls. Aphid populations were very low during 1991/92 season, raising only 0.5 aphid per axis in september. The most important aphid was Rophalosiphum padi lollowed by D. noxia. The iatter one produced only minar damage, aflecting principally the weight of the grains.

1 Estación Experimental La Platina (INIA), Casilla 439, Correo 3, Santiago, Chile.
2 Estación Experimental Intihuasi (INIA). Casilla 36-B. La Serena. Chile,